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昆虫神经生物学研究技术:细胞内记录 总被引:1,自引:1,他引:1
细胞内记录是昆虫神经生物学研究中的常用技术。它用来获得神经元兴奋和抑制过程及神经脉冲产生机制的信息。该技术的特点是把一根微电极的顶尖插入到神经细胞内进行电生理记录 ,这根电极还能用于向膜内输入电流。作者以对蝗虫Schistocercagregaria后胸神经节内的 2个运动神经元的活性记录为例介绍了这一技术 相似文献
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昆虫体内共生物的功能及进化 总被引:11,自引:0,他引:11
<正> 一、共生的类型及研究历史 两种生活在一起的生物彼此互利的现象称为共生(symbiosis)。根据二者的空间关系可分为体外共生、体表共生和体内共生三类。体外共生的现象古已知之,如蚜虫和蚂蚁的互惠便是典型的一例。体表共生是指共生物附着在宿主的体表,如以木质植物隧道中真菌为食的刺胫小蠹能把真菌孢子携带于体壁上的菌穴 相似文献
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由德国埃尔兰根-尼恩贝格大学的JurgenBuning著,Chapman&Hall出版社1994年出版。16开400页。全书分3部分:1.序言;2内口式昆虫的卵巢;3.外口式昆虫的卵巢。附参考文献、种类索引及主题索引。在诸多现代害虫防治理论中,昆虫繁殖生理学是十分重要的基础理论。该书在发现昆虫卵巢结构和功能的基础上,讨论了昆虫卵黄发生前卵巢的生长和演化,阐述了昆虫卵巢的外胚层,主要集中论述了生殖细胞及其与中胚组织的分化和相联的关系。该书有3个特点:1.对各目的昆虫卵巢进行了详细的比较研究;2.建立了昆虫卵巢变异的系统进化模式;3.结… 相似文献
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W Schwemmler 《Bio Systems》1980,12(1-2):111-122
The leafhopper Euscelis incisus K (Homoptera) hosts two types of obligate intracellular symbionts (endocytobionts). The DNA molecular weight (approximately 10(8)) of endocytobionts corresponds to that of the mitochondria and plastids. They are transmitted to the next host generation by incorporation between the egg coat and egg cell in the form of an infection mass. Excision of the infection mass results in cephalothorax embryos which lack the abdomen. Endocytobionts synthesize metabolites such as vitamins, amino acids for the hists using their waste products such as urea and uric acid. The endocytobionts regulate pH, osmotic pressure and certain endogenous rhythms of their hosts. This implies that the leafhopper endocytobionts represent for the host cell not only nutrition but also genomic supplement. According to this hypothesis, the structure, function and information of endocytobionts and eukaryotic DNA-containing cell organelles are analogous; these analogies indicate that endocytobionts may provide a model for molecular analysis of eukaryotic cell system. "Endocytobiology" consequently represents a modern field of research between symbiosis and cell biology. 相似文献
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Four arginaseless mutants of Neurospora crassa have been isolated. All carry mutations which lie at a single locus, aga, on linkage group VIIR. A study of aga strains shows the arginase reaction to be the major, perhaps the only, route of arginine consumption in Neurospora other than protein synthesis. Ornithine-δ-transaminase, the second enzyme of the arginine catabolic pathway, is present and normally inducible by arginine in aga strains, and ornithine transcarbamylase, an enzyme of arginine synthesis, also has normal activity. Arginine inhibits the growth of aga strains. The inhibition can be reversed by spermidine, putrescine (1,4-diaminobutane), or ornithine. The results suggest that ornithine is the major source of the putrescine moiety of polyamines in Neurospora, and that putrescine is an essential growth factor for this organism. The inhibition of aga strains by arginine can be attributed to feedback inhibition of ornithine synthesis by arginine, combined with the complete lack of ornithine normally provided by the arginase reaction. 相似文献
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This review compares new developmental models on flowering andother vascular plants with evolutionary hypotheses formulatedby Agnes Arber (18791960) and like-minded botanists.Special emphasis is laid on philosophical basics such as perspectivism,pluralism about evolutionary modelling, continuum way of thinking,and fuzzy logic. Arber's perspective is best labelled as F uzzyA rberian M orphology (FAM Approach). Its proponents (FAMmers)treat structural categories (e.g. roots, shoots,stems, leaves, stipules)in vascular plants as concepts with fuzzy borderlines allowingintermediates (including transitional forms, developmental mosaics).The FAM Approach complements Cla ssical Plant M orphology (ClaMApproach), which is the traditional approach in botany. ClaMproponents (ClaMmers) postulate that the structuralcategories of vascular plants are regarded as concepts withclear-cut borderlines and without intermediates. However, duringthe evolution of vascular plants, the root-shoot distinctionand the stem-leaf distinction have become blurred several timesdue to developmental changes, resulting in organs with uniquecombinations of features. This happened, for example, in thebladderworts (Utricularia, Lentibulariaceae). When focusingon the leaf, the FAM Approach is identical toArber's partial-shoot theory of the leaf and Sinha'sleaf shoot continuum model. A compound leaf canrepeat the developmental pathway of the whole shoot, at leastto some degree. For example, compound leaves of Chisocheton(Meliaceae)with indeterminate apical growth and three-dimensional branchingmay be seen as developmental mosaics sharing some growth processeswith whole shoots! We focus here on the FAM Approach becausethis perspective is especially promising for developmental geneticistsstudying flowering and other vascular plants. Copyright 2001Annals of Botany Company Review, body plan, developmental mosaics, leaf development, history of botany, homeosis, homeotic genes, Lentibulariaceae, morphological evolution, process morphology, stipules, Utricularia, flowering plants 相似文献
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Margretta R. Seashore 《The Yale journal of biology and medicine》1984,57(3):440-Jun;57(3):440
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W. W. Howells 《American anthropologist》1950,52(4):542-544